docker_pulls

#!/usr/bin/env bash

# make bash behave
set -euo pipefail
IFS=$'\n\t'

# constants
stdout=1
stderr=2
success=0
badusage=64

jq=$(which jq)

# outputs usage message on specified device before exiting with provided status
usage() {
  cat <<'E_O_USAGE' >&"$1"
usage: docker_pulls repo [since]

    repo : a citusdata Docker Hub repository name
    since : a date (optional) in YYYY-MM-DD format

docker_pulls outputs a CSV-formatted pull total for a given repo in citusdata's
org. As Docker Hub can only provide the total number of downloads for all image
versions since the beginning of time, that is what is emitted. Passing the most
recent time point's date as the 'since' parameter will cause this program to
exit without emitting any rows if that parameter is on or after today's date.
E_O_USAGE

  exit "${2}"
}

if [ "$#" -eq 1 ]; then
  if [ "${1}" = '-h' ]; then
    usage $stdout $success
  fi
  since="2016-01-01"
elif [ "$#" -eq 2 ]; then
  since="${2}"
else
  usage $stderr $badusage
fi

today=$(date "+%Y-%m-%d")

echo '"os","release","name","pg_version","version","date","total_downloads"'

if [[ "${since}" > "${today}" || "${since}" == "${today}" ]]; then
  exit
fi

repo=${1}
repourl="https://hub.docker.com/v2/repositories/citusdata/${repo}/"

curl -sf "${repourl}" |
  ${jq} -r "include \"pkg\"; makepullrow(\"${repo}\") | @csv"